What kind of knot is this? [ANSWERED]

[wikakaru]

IMG_0674.JPG

I thought it might be two scaffold knots (https://www.netknots.com/rope_knots/scaffold-knot) tied together, but the tails go the wrong way. Anyone have any ideas? And if you know this knot, how do you untie it? I was always taught that a good knot is easy to tie AND to untie, but this one has me stumped.

FYI, it was used on a kayak to tie the rudder kick-up line to a length of bungee.

Smooth sailing,

Jim

[John Stone]

Not sure. But it looks like the same knot used by Cape Horn Marine Products to tie the ends together of 3/8" shockcord that secures the servo blade to the lower quadrant unit. I wonder if it a shock cord specific knot....

[barfwinkle]

Double Fishermans kanot

[tartansailor]

It's also great for making a loop.
Dick

[wikakaru]

Double Fishermans kanot

You get the prize! Thanks! Now that I know the name it's easy to Google. Here's a good illustration: https://www.101knots.com/double-fishermans-knot.html

Based on the way the knot is tied, it looks like I should be able to slide the two sections apart to loosen it up to untie, but it doesn't want to budge. Must be something about the bungee that is keeping it stuck together.

Smooth sailing,

Jim

[mgphl52]

Must be something about the bungee that is keeping it stuck together.

Taken from the link you posted:

knot.JPG

[John Stone]

As mentioned it looks to be the same knot used to secure the Cape Horn servo blade. I can tell you it's tough to untie but doable. I did it hove-to. Required surgery on the cabin sole. Took awhile. Required a marlinspike. I replaced the bungee with some 3/8" I had on hand. It seems to hold pretty well.

Here is a photo of the knot. Looks similar to me.

[Ab9lz]

As mentioned above, a double fishermans. This knot is especially useful on slippery cordage as it doesn't roll under a load like a simple overhand will. The triple version is recommended if you are tying really slick stuff like dyneema.
Prior to sewn slings, it was popular with climbers.

[Paul D.]

It is a double fisherman. I've used it on ropes courses to make up slings as they can be adjusted in size to lengthen or shorten. It is difficult to untie but can be slid apart and then worked on with a fid. Sit down and make a cup of tea if so. It is also used to tie cordage for the same purpose - adjusting the size of the loop formed. Menogyn special cord (ceremonial bracelets) are tied with this knot. In general it is similar to a Prussik.
Pros - it won't undo, strong (I'd be curious about its braking strength relative to the line) and as mentioned, allows adjustment of loop size
Cons - difficult to untie, takes a fair bit of line to make it up as well.

We should totally have a knot thread every so often!

[wikakaru]

Thanks, all, for the input! This is a knot I'd never come across in 50 years of sailing, nor really had a need to use before. I don't fish, so I never had to worry about tying slippery nylon fishing lines together. But now I will keep it in my repertoire just in case. You know--the right tool for the job and all that.

Smooth sailing,

Jim

[John Stone]

Looks like the knot on the Cape Horn is a single fisherman vice double fisherman. I don’t think you could fit a double in that small space. Works the same but perhaps the double is a little more secure…like single sheet-bend vs a double? I wonder if double is less difficult to untie since more surface area in contact during tension?

[barfwinkle]

I wonder if double is less difficult to untie since more surface area in contact during tension?

In my experience, that answer would be a big fat NO! Once they are loaded, they are very difficult to get un-tied. It can be done, but its tough.